Queen honeybees (Apis mellifera) were reared using undrawn artificial queen cups of 12-mm internal length and 9-mm opening diameter and different conditions of cell priming and larval positioning or orientation. Percentage acceptance (PA) differed significantly (P<0'015) with type of priming, being 55% without royal jelly (RJ) priming, 75% with 8 ~tl pure RJ and 85% with 8 ~ll dilute RJ). There was no significant difference in acceptance of larvae transplanted to cells with a candy seal over the entrance (PA = 73%) and larvae placed in a cell without a seal (PA = 80%). The association between larval position and transplant acceptance was significant at P = 0'01. For larvae located centrally, PA = 75-81% with non-inversion of larvae (controls), 50% with complete inversion and 33% with 90° rotation to bring the dorsal surface of the larva into contact with the royal jelly. For larvae located on the cell wall, PA = 24%; the host bees remodelled the queen cup around each larva to produce a new cell at 45° to the original queen-cup axis. The difference in acceptance for larvae of the common local strain of bees (PA = 81%) and larvae de:-ived from a southern European strain (PA = 74%) was not significant.